Photographic shutter.



Patented Dot. 3|, [899. H. B. CARLTON & E. F. HATHAWAY.

PHOTUG'RAPHIC SHUTTER.

(Application filed Jan. 3, 1899.) (No Model.) 3 SheetsSheet l,

Mzzior n0."636,224. I Patented 0m. 31, I899. H. B. CARLTON & E. F.HATHAWAY.

PHOTOGRAPHIG SHUTTER.

(Application filed Jun. 3, 1899) {No Model.) 3 Sheets-Sheet 2,

No. 636,224. Patented Oct. 3|, I899. H. B. CARLTUN 8:. E. F. HATHAWAY.

PHDTOGRAPHIC SHUTTER. (Application filed .mi. 3, 1899.)

3 Sheets8heet 3,

(No Model.)

m unn \w z====llllrlllllll IKVIARVEY B. CARLTON AND EDeAR E. 'HATHAWAY,OE ROCHESTER, NEw

YORK, ASSIGNORS To THE ROCHEsTER CAMERA AND SUPPLY COM- PANY, OF SAMEPLACE.

PHQTOGRAPl-HG Si-EUTTER.

SPECIFICATION forming part of Letters Patent No. 636,224, dated October31, 1899.

Application filed January 3, 1899. Serial N0. 700,995. (No model.

T0 at whom it may concern.-

Be it known that we, HARVEY B. CARLTON and EDGAR F. HATHAWAY, citizensof the United States, residing at Rochester, in the county of Monroe andState of New York,have invented new and useful Improvements inPhotographic Shutters, of which the following is a specification.

This invention relates to photographic shut ters, and particularly tothat class of such de vices wherein two overlapping sh utter-leaves,each having an aperture adapted to be brought into coincidence with thelens-tube, are so arranged as to normally cover the lens-tube to excludethe light from the camera, means be ing provided for moving saidshutter-leaves one past the other to bring their apertures intoalinement with the lens-tube to permit the passage of the lighttherethrough and then return them to their normal position to excludethe light, both hand-operated and automatic means being provided forregulating the length of time the shutter-leaves remain open to governthe length of the exposure or the period of time during which the lightis permitted to enter the camera.

The present invention has for its object,

first, to provide novel mechanism for actuating the shutter-leaves insuch manner that they are instantly opened and after having remainedopen the desired length of time are instantly closed, whereby the lengthof exposure is rendered practicallyindependent of the time occupied bythe shutter-leaves in opening and closing, thus giving the sides of thesensitized plate or film the same length of exposure that is given toits center; second, to provide novel mechanism for operating theshutter-leaves by means of which the speed of the shutter-leaves intheir opening and closing movements is rendered invariable; third, toprovide, in combination with a motive device operating first to Open thesh u tter-leaves and then close them, a novel retarding deviceconstructed to determine the length of time intervening between themoment the shutter-leaves are opened and the moment they begin to close,and, finally, it has for its object to provide improved mechanismoperating in a novel manner for controlling the action of theshutter-leaves and tosimplify the construction, cheapen the pro-- dnotion, and render more reliable and certain this class ofphotographicshutters generally.

To these ends our invention consists in the features and in theconstruction, combination, and arrangement of parts hereinafterdescribed, and particularly pointed out in the claims following thedescription, reference being had to the accompanying drawings, forming apart of this specification, Wllllil Figure 1 is a view in frontelevation of our improved shutter. 2 is a side elevation of the same.Fig. 3 is a rear elevation, the case being partially removed to show themo tive device. Fig. l is a detail view in elevation, showing themechanism set for actuating the shutter-leaves and just in the not ofopening the latter. 5 is a similar view showing the shutter-leavesopened and the parts in position for holding them open. Fig. 6 isanother similar view showing the shutterleaves closed and the parts intheir corresponding position. Fig. 7 is a vertical central sectionalview; and Fig. 8 is adetail perspective view of the motive device, theparts being shown separated.

Referring to the drawings, the numeral 1 indicates a flat circularcasing provided upon its periphery with an annular rearwardly-projectingflange 2, on the rear end of which is fixed a cover-plate 3. This casingcontains the shutter-leaves and their immediate operating parts. Fittedin an aperture formed centrally in the cover-plate 3 is the lens-tube 4,which is preferably threaded exteriorly, as at 5, whereby it may beremovably fitted in an interiOrly-threaded sleeve 6, lined in the frontboard 7 of the camera (see 7) in a usual and well-known manner. lVithinthe lens-tube is arranged a lens or plurality of lenses of any approvedor preferred construction. Attached to the front side of the coverplate3, immediately in front of the lens-tube, is an iris diaphragm S ofwell-known and ordinary construction and provided with an operating-arm9, having an upturned end 10, constituting a pointer which is adapted toregister with any one of a series of graduations 11, marked on the frontof the casing 1. By turning the arm 9 the size of the aperture of thediaphragm is adjusted to suit the will of the operator in an ordinarymanner, and the relative size of the aperture will be indicated by thepointer 10. There is nothing novel in the construction of thisdiaphragm, and it is only slightly indicated and briefly alluded to toshow its location and arrangement relative to the shutter-leaves. Formedcentrally on the front of the casing 1 is an annular interiorlythreadedflange 12, in which is screwed a sleeve 13, carrying an objective lens14, and formed in the casing 1, concentrically with the flange 12, is aview-apertn re 15. To the rear side of the casing 1 and upon oppositesides of the view-aperture 15 are pivoted intermediate their ends leversl6 and 17, the pivots 18 of said levers being arranged slightly oneabove the other, as most clearly shown in Figs. 4, 5, and 6. Theopposite ends of said levers are loosely attached to the shutter-leaves19 and 20. As shown, each of said shutter-leaves consists of a thin leafapproximately rectangular in shape and provided at one end with anaperture 21, and said aperture should be .at least as large as theviewaperture 15. The shutter-leaves are formed of opaque and preferablyof very light materialsuch as hard rubber, for example. The upper endsof the levers 16 and 17 are attached to the upper opposite corners ofone of the shutter-leaves, as 15), while the lower ends of said leversare in like manner attached to the other shutter-leaf 20. As aconvenient means for loosely connecting the levers and shutter-leaves weprefer to turn up the ends of the levers, as at 22, and loosely insertsuch turned-up ends in perforations 23, formed at appropriate points insaid shut-- ter-leaves. "he shutter-leaves should be so connected to thelevers that their apertures 21 normally lie on opposite sides of theviewaperture 15, or, in other words, so that their solid portionsnormally cover said view-aperture, and to hold them in such a positionwe provide a spring 24, which operates in a manner which willhereinafter be described. One of the shutter-leaves being carried by theupper ends of the levers and the other shutterleaf by the lower endsthereof, it will be readily understood that as said levers areoscillated about their pivots the shutter-leaves will slide one past theother in nearly a right line. Hence when the levers are swung from theposition shown in Fig. a (in which the shutter-leaves are in theirclosed position) to the position shown in Fig. 5 the sh utter-leaveswill be moved past one another in a direction to bring their aperturesinto coincidence, thus uncovering the view-aperture to admit the lightto the camera and make an exposure. As soon as released the spring 2%will instantly return the shutter-leaves to the position shown in 4, orto closed position.

We have shown and described a type of shutter-leaves and the action ofthe same for use with our photographic shutter; but we wish it to beunderstood that we may use any of the ordinary and well-kn own types ofsh ntter-leaves in connection with our controlling and operatingmechanism, which forms the chief part of our invention.

\Ve have devised improved mechanism for actuating the sh utter-leavesand for controllingtheir action in a novel manner, which will now bedescribed. This part of the apparatus comprises a motive device andcontrolling mechanism so constructed and arranged that theshutter-leaves may be actuated to effect an instantaneous, time, or bulbexposure and is constructed as follows: Formed with or attached to thecasing 1 is a cylindricalcasing26, which incloses the motive device. Asshown most clearly in Figs. 7 and 8 of the drawings, the numeral 27indicates a spring-barrel having coiled therein a convolute spring 28.The barrel is formed with a forward ly-projecting sleeve 29, which isjournaled in an aperture formed centrally in the front of the case 20.The sleeve is open at its opposite ends, and loosely passingtherethrough is a shaft 30, on the forward end of which is rigidly fixedan adjusting-disk 31. On the opposite end of the shaft 30 is keyed acam-plate 32, on the forward face of which is fixed a pin 33. The pin 33is adapted to engage any one of a series of pin-holesifit, formed in therear face of the spring-barrel 27 to lock said cam-plate andspring-barreltogether, and in order to hold the pin to its seat in thepin-hole in which it may be inserted a coiled spring 35 is disposedabout the shaft 30 and bears at one end against the disk 31 and at itsother end against the end of the sleeve 2.). This spring being placed inposition under compression opet ates to draw the shaft 30,and with itthe cam-plate 32, forward, thus holding the pin seated in one of thepin-holes. By pressing the disk 31 inward the pin will be forced out ofthe pin-hole, and then by turning said disk the cam-plate may be freelyrotated, so as to change its position relatively to the spring-barrel,and by then releasing the disk the spring 35 will again draw the camplate and spring-barrel together, forcing the pin into one of thepin-holes and locking the cam-plate and spring-barrel in their adjustedpositions for the purpose hereinafter described. Adapted to freelyrotate in an annular groove 36, formed in the inner face of the front ofthe casing 26, is a ringll7, that is held to its seat by thespring-barrel 27. Keyed to the outer end of the sleeve 25) is a disk 38,which is provided on its rear face with a hub 39, arranged to bearagainst the front of the casin 26, and thus hold the parts in place. Asdescribed, the disk 31 and cam-plate 32 are permanently fastenedtogether rigidly, and the spring-barrel 27 and disk are in like mannerfastened together. Hence when the adjustment-disk 31 is in its normalposition the pin 33 will be in engagement with one of esaeea thepinholes in the spring-barre1, and then the adj ustment-disk 3l, disk33, spring-barrel 2'7, and cam-plate 32 will all be locked together andmust rotate as one. The periphcry of the spring-barrel 27 is recessed ormutilated for a suitable distance, as at 40, forming two shoulders 41and 42, and another recess 43, shown in the drawings as beingpractically semicircular in shape, is cut in the periphery of thespring-barrel a short dis tance from the recess 40, leaving between themwhat constitutes, in effect, a cam 44. The cam-plate 32 is formed with aperipheral cam portion 45, having an abrupt shoulder 46, and by turningthe cam-plate relatively to the spring-barrel the slot in the latterwill be more or less covered, and thereby lengthened or shortenechby thecam portion of the cam-plate, or, in other words, the shoulders 42 and46 will be brought nearer together or farther apart,for the purposepresently made apparent. The cam-plate is also provided with a shoulder47,which is adapted to abut a pin 48 on the face of the spring barreland prevent the camplate from being turned too far. On the rear face ofthe ring 37 is fixed a pin 49, which projects into the recess 40 betweenthe shoulders 41 and 42 of the spring-barrel, and said plate is also provided with a peripheral perforated ear 50, to which is pivotallyconnected one end of an arm 51, the other end ofsaid arm being connectedto the plunger of a dash-pot. Said dash-pot consists of ahollow cylinder52,1igidly attached to one side of the front of the casing l, and isprovided at its lower end wiih an air escape or vent 53. (See Fig. 2.)The size of the escape-opening in the vent may be regulated by a screw54, of ordinary and well-known construction. In the cylinder 52 isadapted to freely reciprocate an inverted cylindrical cup constitutingthe plunger. Owing to the smallness of the air-vent it will be evidentthat the plunger can descend by the application of a moderate force butslowly, and this is the retarding device before referred to and theoperation of which will hereinafter be described. To the front of theface of the disk 38 is fixed a pin 55, which acts as a stop to hold themotive device in its set position in the following manner: Pivoted tothe front face of the casing l is a pivoted dog 56, one end of which isformed with a square shoulder 57, that is adapted to engage behind thepin 55 and hold the motive device in its set position. The other end ofsaid dog loosely rests in the bifurcated end of a hollow plunger 58,that is arranged to freely reciprocate in a hollow cylinder 59, rigidlyattached to one side of the front face of the casing 1. The lower end ofthe cylinder is provided with a nipple (50, over which is fitted one endof a rubber tube 61, provided at its opposite end with a hollow elasticbulb, as usual. The dog 56 is also provided with a pin 62, which isengaged by the forked end of a pivoted releasing-lever 63,

provided at its opposite end with a finger 64. By these means the dog 56can be thrown into and out of engagement with the pin 55 either by meansof the bulb or directly by hand. The dog is normally held in engagementwith the pin 55 by aspring 65, one end of which is fixed and the otherbears against the pin 62 on the dog, thus operating to throw theshoulder 57 of the dog up, so as to engage the pin. The connectionbetween the shutter-leaves and the motive device consists of an arm 66,one end of which is pivotally connected to one of the levers, as 17,while the other or free en d is provided with a hook-shaped flange 67underneath, which bears the end of the spring 24-, before described. Thespring 24 is attached at one end to the casing and at its other endbears beneath flange 67 on the arm 66, and in order to increaseitsresiliency the spring is preferably provided intermediate its ends witha coil or loop 25. The spring operates to lift the arm 66 lengthwise,thus also moving the shutter-leaves to their closed position whennothing obstructs such movement of the arm. In order to set the motivedevice, a handle or fii'iger-piece 63 is formed on or attached to thedisk 38. As clearly shown in Fig. 8, the pin-holes 34 in thespringbarrel are set at different distances apart, and this is for thereason that by changing the pin of the cam-plate from one pin-hole toanother the action of the motive mechanism, and consequently thecharacter of the exposure effected, will be altered, as will beexplained hereinafter. For example, when the pin is inserted in theholect the parts will be set for bulb exposure, when inserted in the hole 5the parts will be set to effect an instantzmeous exposure, and wheninserted in either of the holes a the parts will be set for timeexposure, the different holes 0 being for different lengths of timeexposures-as, for example, seconds and fractions of seconds.Asbeforedescribed,thepinischanged from one pin-hole to another bypressing in the disk 31 and then turning it to turn the cam-plate to theproper position to bring the pin opposite the pin-hole desired. In orderthat the operator may do this with ease and certainty, we mark certaincharacters on the front face of the setting-disk 38, which correspondexactly in position with the pin-holes and form a peep-hole (39 in thedisk 31, through which the characters may be viewed one ata time. Thusif an instantaneous exposure is desired the disk 31 will be pushed inand turned until the character 1 appears opposite the peep-hole. Thenthe pin 33 will be opposite the pin-hole b, and by releasing the diskthe spring 35 will force the pin into the pinhole and the parts will bein position to effect an instantaneous exposure.

The operation of this part of iheinvention is as follows: \Vhen theparts are in a state of rest, or, in other words, the camera is not inactual use, the parts will be in the position shown in Figs. 3 and 6,and the end of the arm 66 will then rest in the recess 43, andconsequently the shutter-leaves will be closed. Let it be assumed thatit is desired to take a time exposure. The disk 31 is then pushed in andturned until the character on the setting-disk indicating the timeexposure of the length desired appears through the peep-hole 69, whenthe disk is released and the pin 33 enters the proper pin-hole. Thisoperation fixes the cam-plate in such a position relatively to thespring-barrel that the shoulder 46 of the cam-plate is brought within acertain distance of the shoulder 42 of the spring-barrel. The disk 31,setting-disk 38, spring-barrel 27, and cam-plate 32 now stand lockedtogether, so as to rotate in unison. By now turning the setting-disk 38by means of the handle 68 in the direction of the ar row, Fig. 1, thesetting-disk, disk 3l,springbarrel, and the cam-plate are all partiallyrotated into the position shown in Fig. 4. This operation winds up thespring 28 in the spring-barrel and carries the pin 55 on thesetting-disk around toward the left, and in its movement said pinstrikes against the edge of the upper end of the dog 56 and depresses ituntil the pin 55 has passed the end of the dog, whereupon the dog isreturned to its former position by its spring 65, and the pin 55 bearsagainst the shoulder 57 of the dog, thus holding the parts in their setposi tion with the spring 28 wound up. At one part of the operation theshoulder 46 of the cam-plate strikes the pin 49, carried by the loosering 37, and moves said pin and ring toward the left with it. Previousto this, however, the cam eat on the spring-barrel has struck anddepressed the end of the arm 66 and swept over it until the shoulder 42has passed the arm, whereupon the arm was returned to its formerposition by the spring 24 and entered the recess 40 in the springbarrel,as shown in Fig. 4. This movement communicated to the arm 66 did notaffect the shutter-leaves in any manner, as the arm was given no endwisemovement, but merely had its upper end pushed aside. The arm in itsnormal position bears atits upper edge against a pin 70, fixed in thecasing 1. The

parts are now all set and ready to effect the exposure. This is done bydepressing; the

free end of the releasing-lever 63, as shown by dotted lines in Fig. 5,which raises the adjacent end of the dog 56 and depresses the upper endthereof, throwing the shoulder 57 down below the pin 55. Upon this thespring 28 immediately turns all the parts, excepting the ring 37, in thedirection of the arrow, Fig.

5, and the shoulder 42 immediately strikes.

the end of the arm 66 and forces it down into the position shown in Fig.5, which instantly opens the shutter-leaves. The cam 44 swiftly sweepsover the end of the arm 66 until it strikes the pin 49, carried by theloose ring 37. It will be remembered that this ring is connected to thedash-pot plunger by the arm 51. Hence when the pin 49 was moved aroundinto position in setting the mechanism the plunger was raised. Ittherefore follows that when the swiftly-moving'cam 4-4: strikes said pin49 in order to move said pin along with it it must force d own saidplunger and in doing so its movement is retarded, and during theremainder of its movement over the end of the arm 66 its speed isrelatively slow. \Vhen the cam set has completely passed over the end ofthe arm, said arm is immediately raised up into the recess 43 of thespring-barrel by its spring 24, whereupon the shutter-leaves areinstantly closed, completing the exposure. The parts are then in theposition shown in Fig. 6. From the foregoingit will be readilyunderstood that when the arm (36 is struck by the cam 44 the shutter-leaves are instantly opened and that the cam passes so swiftlyover the end of the arm that the shutter leavcs have remained open butan inconceivably brief period of time when the cam strikes the pin &9sobrief, in fact, as to form no practical part of the exposure. When thecam 44: strikes the pin 49, however, it is retarded in the mannerdescribed during the rest of itsmovementovertheendofthearm. Hence it isthe duration of the exposure is determined by how soon the cam strikesthe pin 49 after depressing the arm to open the shutter-leaves, and thisis determined by so setting the cam-plate as to cause its shoulder 46 tosooner or later engage said pin and move it forward in setting themotive device, for the sooner said shoulder engages said pin the nearerthe pin will be moved toward the end of the arm and the sooner,therefore, will it be engaged by the cam, thereby retarding the camduring a greater portion of its sweep over the end of the arm andholding open the shutter-leavesa corresponding period of time. From allof which it follows that by causing the pin 33 to engage one or theother of the pin-holes c of the spring-barrel the length or duration ofthe time exposure is regulated with great accuracy.

Instead of releasing the dog by means of the hand releasing-lever 56 thesame result could have been accomplished, of course, by compressing theelastic bulb, thus lifting the plunger 58 and with it the end of thedog, and this is true of all the different exposures. It will be notedthat the movement of the shutter-leaves in closing is not retarded, butthat the retarding device operates to retard the motive device, and whenthe moment arrives for closing the shutter-leaves they close instantly.Hence, as has been before stated, the shutter-leaves are both opened andclosed instantly, whereby the sides of the plate or film receive thesame length of exposure as the center, which is not the case in thoseshutters wherein the retarding device operates to cause theshutter-leaves to close more or less slowly, thus causing the center ofthe plate or film to receive a longer exposure than the sides, resultingin a negative a portion of which will have been properly exposed and theother portion over or under exposed, or one part underexposed and theother part overexposed. In the present invention the speed of theshutter-leaves in both opening and closing is invariable, and this istrue of both time and instantaneous exposures.

In making instantaneous exposures the operation is as follows: The disk31 is first pushed in and the cam-plate rotated until the character Iappears through the peep-hole 69 in the disk, when the latter isreleased, whereupon the spring 35 will draw the pin 33 of the cam-plateinto the pin-hole b of the spring-barrel. This will fix the camrelatively to the spring-barrel in such a position that the shoulder 46will be approximately coincident with the shoulder 41. The motive deviceis then set by turning the handle 68 in precisely the same manner beforedescribed, all the same results following excepting that in the presentinstance the shoulder 46 does not strike the pin 49, and the latter,therefore, is not moved toward the left or toward the end of the arm 66.When the exposure is to be made, the dog is disengaged from the pin 55,as before, whereupon the parts will rotate, and the shoulder 42 willimmediately force down the arm 60, instantly opening the shutter-leaves.The cam 4-iwill swiftly sweep over the end of the arm, and the pin 49not being in its path to interrupt it its movement will be one swiftsweep over the end of the arm, permitting the latter to immediately fiyup into the recess 43 and instantly closing the shutter-leaves, the timethe shutter -leaves remain open being the time the cam 44 occupies tomake one uninterrupted swift sweep over the end of the arm, which inpractice is but a small fraction of a second.

Having described our invention, what we claim is- 1. In a photographicshutter, the combination with a device for admitting the light to andexcluding it from the camera to effect the exposure, of a motive devicefor instantly opening the exposing device and temporarily holding itfully open, a spring for instantly closing the exposing device, aretarding device for retarding the movement of the motive device afterit has completely opened the exposing device and thereby temporarilyprevent the spring from closing the latter until the motive device hascompleted its movement, and means for throwing said retarding deviceinto operation at different periods of the movement of the motive deviceto vary the duration of the exposure, substantially as described.

2. In a photographic shutter, the combination with a device foradmitting the light to and excluding it from the camera to effecttheexposure, of a motive device for instantly opening the exposingdevice and temporarily holding it fully open, a spring for instantlyclosing the exposing device, a retarding detive device after it hascompletely opened the exposing device and thereby temporarily pre ventthe spring from closing the latter until the motive device has completedits movement, means for throwing said retarding de vice into operationat different periods of the movement of the motive device to vary theduration of the exposure, and means for throwing said retarding deviceentirely out of operation at the will of the operator, substantially asdescribed.

3. In a photographic shutter, the combination with a device foradmitting the light to and excluding it from the camera to effect theexposure, of a motive device for instantly opening the exposing deviceand temporarily holding it open, a spring for instantly closing it, andmeans for varying the speed of the motive device at different periods ofits movement to regulate the duration of the exposure, substantially asdescribed.

4. In a photographic shutter, the combination with a device foradmitting the light to and excluding it from the camera to effect theexposure, of a motive device for instantly opening the exposing deviceand temporarily holding it open, a spring for instantly closing it,means for varying the speed of the motive device at different periods ofits movement to regulate the duration of the exposure, and means forthrowing said speed regulating movement into or out of operation,substantially as described.

5. In a photographic shutter, the combination with a device foradmitting the light to and excluding it from the camera to effect theexposure, of a motive device for instantly opening the exposing deviceand temporarily holding it open, a spring for instantly closing it,means for varying the speed of the motive device at different periods ofits movement to regulate the duration of the exposure,'and means underthe control of the operator for throwing the said speed regulating meansinto operation at any predetermined period of the movement of the motivedevice, sub stantially as described.

6. In a photographic shutter, the combination with two aperturedswinging shutterleaves, arranged to swing laterally past each other tobring their apertures into and out of coincidence, of a motive devicefor instantly opening the slrutterdeaves, a spring for instantly closingthem, a retarding device for retarding the movement of the motive deviceafter it has completely opened the shutterleaves and thereby temporarilyprevent the operation of the shutter-leaf-closing mechanism until themotive device has completed its movement, and means for throwing saidretarding device into operation at different periods of the movement ofthe motive de vice to vary the duration of the exposure, substantiallyas described.

'7. In a photographic shutter, the combination with two aperturedswinging shuttervice for retarding the movement of the inoleavesarranged to swing laterally past each other to bring their aperturesinto and out of dependent of the cam, a dash-pot connected coincidence,of motive device for instantly opening said shutter-leaves, a spring forinstantly closing them, a retarding device for retarding the movement ofthe motive device after it has opened the shutter-leaves and therebytemporarily prevent the operation of the shutter-leaf-elosing mechanismuntil the motive device has completed its movement, means for throwingsaid retarding device into operation at different periods of themovement of the motive device to vary the duration of the exposure, andmeans for throwing said retarding device out of operation at the will ofthe operator, substantially as described.

S. In a photographic shutter, the combination with two aperturedswinging shutterleaves arranged toswing laterally past each other tobring their apertures into and out of coincidence, of an arm foractuating said shutter-leaves, a partially-rotatable springactuated camfor depressing said arm to open the shutter-leaves, a spring operatingto close the shutter-leaves when the cam has passed over the arm, andmeans for retarding the speed of the cam to defer the action of thespring in closing the slnitter-leaves, substantially as described.

9. In a photographic shutter, the combination with two aperturedswinging shutterleaves arranged to swing laterally past each other tobring their apertures into and out of coincidence, of an arm foractuating said sh utter-leaves, a partially-rotatable spring-actuatedcam for depressing said arm to open the shutter-leaves, a springoperating to close the shutter-leaves when the cam has passed over thearm, and means for retarding the speed of the cam at different periodsof its move ment to defer the action of the springin closing theshutter-leaves, substantially as described.

10. In a photographic shutter, the combination with two aperturedswinging shutterleaves arranged to swing laterally past each other tobring their apertures into and out of coincidence, of an arm foractuating said sh u tter-leaves, a partially-rotatable spring-actuatedcam for depressing said arm to open the shutter-leaves, a springoperating to close the shutter-leaves when the cam is passed over thearm, and a yielding resistance adapted to be placed in the path of thecam at varying distances therefrom to retard its movement and deter theaction of the spring in closing the shutter-leaves, substantially asdescribed.

11. In a photographic shutter, the combination with two aperturedswinging shutterleaves arranged to swing laterally past each other tobring their apertures into and out of coincidence, of an arm foractuating said shutter-leaves, a partially-rotatable spring-actuated camfor depressing said arm to open the shutter-leaves, a spring operatingto close the shutter-leaves when the cam has passed over the arm, arotatable ring adapted to rotate into said ring, a pin carried by saidring, and means for rotating said ring to place said pin in the path ofthe cam, whereby, when the cam has depressed the arm to open theshutter-leaves it will strike said pin and be retarded in its furthermovement by the dash-pot, substantially as described and for the purposespecified.

12. In aphotographic shutter, the combination with two aperturedswinging shutterleaves arranged to swing laterally past each other tobring their apertures into and out of coincidence, of an arm foractuating said shutter-leaves, a partially-rotatable spring-actuated camfor depressing said arm to open the shutter-leaves, a spring operatingto close the shutter-leaves when the cam has passed over the arm, arotatable ring adapted to rotate independentlyof the cam, adash-potconnected to said ring, a pin carried by the ring, and means under thecontrol of the operator for rotating the ring to place the pin in thepath of the cam to retard the movement of the latter, substantially asdescribed and for the purpose specified.

13. Inaphotographic shutter, the combination With two apertured swingingshutter leaves arranged to swing laterally past each other to bringtheir aperture into and out of coincidence, of an arm for actuating saidshut ter-leaves, a partially-rotatable spring-actuated cam fordepressing said arm to open the shutter-leaves, aspring operating toclose the shutter-leaves when the cam has passed over the arm,arotatable ring, a dash-pot connected to the ring, a pin carried by thering, a camplate arranged to rotate with the cam and having a shoulderarranged to move the pin into the path of the cam, whereby the cam afterit has opened the shutters strikes the pin and is retarded in itsfurther movement by the dash-pot, substantially as described.

It. In a photographic shutter, the combination with two aperturcdswinging shutterleaves arranged to swing laterally past each other tobring their apertures into and out of coincidence, of an arm foractuating said shutter-leaves, a partially-rotatable spring-actu atedcam for depressing said arm to open the shutter-leaves, a springoperating to close the shutter-leaves when the cam has passed over thearm, a rotatable ring,a dash-pot connected to the ring, a pin carried bythe ring, a camplate arranged to rotate with the cam and having ashoulder arranged to move the pin into the path of the cam, whereby thecam after it has opened the shutter-leaves strikes the pin and isretarded in its further movement by the dash-pot, and means foradjusting the can1-plate relatively to the cam to cause its shoulder tomove the pin a greater or less distance, substantially as described andfor the purpose specified.

15. In a photographic shutter, the combination with two aperturedshutterdeaves arranged to swing laterally past each other to IIO bringtheir apertures into and out of coincidence, of an arm for actuatingsaid shutterleaves, a partially-rotatable spring-actuated cam fordepressing said arm to open the sh utter-leaves, said cam having aseries of pinholes formed in its face, a spring operating to close theshutter-leaves when the cam has passed over the arm, a rotatable ring, adashpot connected to the ring, a pin carried by the ring, a cam-platearranged adjacent to the cam and provided with a stud adapted to engageeither of said pin-holes, a shoulder on the cam-plate arranged to movethe pin into the path of the cam, whereby the cam after it has openedthe shutter-leaves strikes the pin and is retarded in its furthermovement by the dash-pot, and means for adjusting the stud on thecam-plate in either of the holes of the cam at will, substantially asdescribed and for the purposes specified.

10. In a photographic shutter, the combination with two aperturedshutter-leaves arranged to swing laterally past each other to bringtheir apertures into and out of coincidence, of an arm for actuatingsaid shutterleaves, a partially-rotatable spring-actuated cam fordepressing said arm to open the sh utter-leaves, said cam having aseries of pinholes formed in its face, a spring operating to close theshutter-leaves when the cam has passed over the arm, a rotatable ring, adashpot connected to the ring, a pin carried by the ring, a cam-platearranged adjacent to the cam and provided with a stud adapted to engageeither of said pin-holes for yieldingly holding the stud in engagementwith the pinholes, a shoulder on the cam-plate arranged to move the pininto the path of the cam, whereby the cam after it has opened theshutter-leaves strikes the pin and is retarded in its further movementby the dash-pot, and means for adjusting the stud on the cam-plate ineither of the holes of the cam at will, substantially as described andfor the purpose specified.

17. In a photographic shutter, the combination with two aperturedshutter-leaves ar ranged to swing laterally past each other to bringtheir apertures into and out of coincidence, of an arm for actuatingsaid shutterleaves, a rotatable shaft having a turning disk fixed on oneend, a shouldered camplate fixed on the other end, a spring-actuated camloosely sleeved on the shaft and provided on its face with a series ofpin-holes, said cam operating to depress said arm to open theshutter-leaves, a spring for closing the shutter-leaves when the cam haspassed over the arm, a rotatable ring, a dash-pot connected to the ring,a pin carried by the ring, a stud on the cam-plate adapted to fit eitherof the pin-holes in the cam, a spring for moving the shaft endwise tohold the stud in the pin-hole to which it may be adjusted, means forsetting the spring, and a releasing device,

substantially as shown and described and for the purpose specified.

18. In a photographic shutter, the combination with two aperturedshutter-leaves arranged to swing laterally past each other to bringtheir apertures into and out of coincidence, of an arm for actuatingsaid shutterleaves, a rotatable shaft having a turning disk fixed on oneend, a shouldered camplate fixed on the other end, a spring-actuated camloosely sleeved on the shaft and provided on its face wit-ha series ofpin-holes, said cam operating to depress said arm to open theshutter-leaves, a spring for closing the shutter-leaves when the cam haspassed over the arm, a rotatable ring, a dash-pot connected to the ring,a pin carried by the ring, a stud on the cam-plate adapted to fit eitherof the pin-holes in the cam, a spring for moving the shaft endwise tohold the stud in the pin-holes to which it may be adjusted, means forsetting the cam-actuating spring, and a releasing device, the saidturning disk being provided with a peep-hole, and a disk fixed on thesleeve of the cam, said disk being provided with a series of characterscorresponding in position to the pin-holes on the cam, said charactersbeing arranged to be viewed one at a time through the peep-hole in theturning disk, substantially as described and for the purpose specified.

10. In a photographic shutter, the combina tion with two aperturedshutter-leaves ar= ranged to swing laterally past each other to bringtheir apertures into and out of coincidence, of an arm for actuatingsaid shutterleaves, a rotatable shaft having a turning disk fixed on oneend, a shouldered camplate fixed on the other end, a spring-actw atedcam loosely sleeved on the shaft and provided on its face with a seriesof pin-holes, said cam operating to depress said arm to open theshutter-leaves, a spring for closing the shutter-leaves when the cam haspassed over the arm, a rotatable ring, a dash-pot connected to the ring,a pin carried by the ring, a stud on the cam-plate adapted to fit eitherof the pin-holes in the cam, a spring for mov= ing the shaft endwise tohold the stud in the pin-hole to which it may be adjusted, asetting-disk fixed on the sleeve of the cam and provided with a pin, apivoted dog for engaging said pin to hold the parts in their setposition, and a releasing device for disengaging the dog from the pin toput the parts in operation, substantially as described.

In testimony whereof we have hereunto set our hands in presence of twosubscribing wit= messes.

HARVEY B. CARLTON. EDGAR F. HATHAXVAY.

lVitn esses:

HIRAM R. Wool), RAYMOND G. PHILLIPS.

Iio

